> hypothetically reducing the ticket availability towards zero
This is prohibition with extra steps. Granted, you deal with the problem of tainted drugs. But that isn’t the chief issue, and creating a giant hole in the budget aimed exclusively at that harm seems political suicide.
In case it’s not clear, I am in favor of prohibition! The exact lesson I draw from the failure of alcohol prohibition is that drug harm isn’t a major factor in drug users’ choices; you can’t (ethically) reduce demand by making drugs more harmful, and more modern evidence seems to show that making drugs less harmful doesn’t increase use by much either. I believe that drug distribution should be illegal, and drug consumption should be as safe as practical.
If we’re talking about political feasibility, I think replacing harmful street drugs with their pure versions at the point of consumption is politically much closer to “safe injection sites” than it is to “government agents with the job title of Drug Dealer”.
This is prohibition with extra steps. Granted, you deal with the problem of tainted drugs. But that isn’t the chief issue, and creating a giant hole in the budget aimed exclusively at that harm seems political suicide.